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BACKGROUND@#Nowadays, biological tissue engineering is a growing field of research. Biocompatibility is a key indicator for measuring tissue engineering biomaterials, which is of great significance for the replacement and repair of damaged tissues. @*METHODS@#In this study, using gelatin, carboxymethyl chitosan, and sodium alginate, a tissue engineering material scaffold that can carry cells was successfully prepared. The material was characterized by Fourier transforms infrared spectroscopy. In addition, the prepared scaffolds have physicochemical properties, such as swelling ratio, biodegradability.we observed the biocompatibility of the hydrogel to different adult stem cells (BMSCs and ADSCs) in vivo and in vitro. Adult stem cells were planted on gelatin-carboxymethyl chitosan-sodium alginate (Gel/SA/CMCS) hydrogels for 7 days in vitro, and the survival of stem cells in vitro was observed by live/died staining. Gel/SA/CMCS hydrogels loaded with stem cells were subcutaneously transplanted into nude mice for 14 days of in vivo culture observation. The survival of adult stem cells was observed by staining for stem cell surface markers (CD29, CD90) and Ki67. @*RESULTS@#The scaffolds had a microporous structure with an appropriate pore size (about 80 lm). Live/died staining showed that adult stem cells could stably survive in Gel/SA/CMCS hydrogels for at least 7 days. After 14 days of culture in nude mice, Ki67 staining showed that the stem cells supported by Gel/SA/CMCS hydrogel still had high proliferation activity. @*CONCLUSION@#Gel/SA/CMCSs hydrogel has a stable interpenetrating porous structure, suitable swelling performance and degradation rate, can promote and support the survival of adult stem cells in vivo and in vitro, and has good biocompatibility. Therefore, Gel/SA/CMCS hydrogel is a strong candidate for biological tissue engineering materials.
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BACKGROUND: The Id2 gene is an endogenous negative regulator of basic helix-loop-helix factor, which is involved in the cell proliferation, differentiation and existence. Id2 also shows functional diversity in the progression and infiltration of different types of tumors OBJECTIVE: To observe the changes of proliferation and invasiveness of PC-3 human prostate cancer stem cells after shRNA-Id2 transfection. METHODS: PC-3 human prostate cancer stem cells in logarithmic growth phase were harvested to isolate tumor stem cell spheres by serum-free suspension culture. The expression of CD44+CD24-on the surface of tumor stem cells was detected by flow cytometry. The shRNA-Id2 expression vector was constructed and transfected into PC-3 human prostate cancer stem cells. Untransfected PC-3 human prostate cancer stem cells were used as control. At 48 hours after transfection, the expression of Id2 gene and protein in shRNA-Id2 transfected prostate cancer stem cells, NC-shRNA empty vector transfected prostate cancer stem cells and untransfected prostate cancer stem cells were detected by RT-PCR and western blot, respectively. The proliferation and invasion of shRNA-Id2 transfected prostate cancer stem cells and untransfected prostate cancer stem cells were detected by MTT assay and Transwell chamber, respectively. The expressions of E-cadherin, vimentin and Twist were detected by western blot and RT-PCR. RESULTS AND CONCLUSION: Tumor stem cell spheres were successfully isolated by the serum-free suspension culture. The expression rate of CD44+CD24-on the surface of the third-generation PC-3 human prostate cancer stem cells was (85.69±8.96) ％, indicating that the cultured tumor stem cell spheres overexpressed the phenotype of tumor stem cells. At 48 hours after transfection, the expression of Id2 gene and protein was significantly lower in the shRNA-Id2 transfection group than the non-transfection group (P < 0.05) , indicating that the expression of Id2 was successfully interfered with the expression of PC-3 prostate cancer stem cells. The invasive ability of the cells in the shRNA-Id2 transfection group was significantly lower than that in the non-transfection group (P < 0.05). Western blot and RT-PCR detection showed that the expression of E-cadherin, an epithelial marker of PC-3 prostate cancer stem cells, in the shRNA-Id2 transfection group was significantly higher than that in non-transfection group (P < 0.05) , while the expression of vimentin, a marker of mesenchymal stem cells, and Twist, a transcription factor regulating cell-mesenchymal transformation, in the shRNA-Id2 transfection group was significantly lower than that in the non-transfection group (P < 0.05). These findings indicate that RNA interference with Id2 gene can inhibit the proliferation and invasion of PC-3 prostate cancer stem cells by regulating the expression of E-cadherin, vimentin and Twist.
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BACKGROUND: The Id2 gene is an endogenous negative regulator of basic helix-loop-helix factor, which is involved in the cell proliferation, differentiation and existence. Id2 also shows functional diversity in the progression and infiltration of different types of tumors OBJECTIVE: To observe the changes of proliferation and invasiveness of PC-3 human prostate cancer stem cells after shRNA-Id2 transfection. METHODS: PC-3 human prostate cancer stem cells in logarithmic growth phase were harvested to isolate tumor stem cell spheres by serum-free suspension culture. The expression of CD44+CD24-on the surface of tumor stem cells was detected by flow cytometry. The shRNA-Id2 expression vector was constructed and transfected into PC-3 human prostate cancer stem cells. Untransfected PC-3 human prostate cancer stem cells were used as control. At 48 hours after transfection, the expression of Id2 gene and protein in shRNA-Id2 transfected prostate cancer stem cells, NC-shRNA empty vector transfected prostate cancer stem cells and untransfected prostate cancer stem cells were detected by RT-PCR and western blot, respectively. The proliferation and invasion of shRNA-Id2 transfected prostate cancer stem cells and untransfected prostate cancer stem cells were detected by MTT assay and Transwell chamber, respectively. The expressions of E-cadherin, vimentin and Twist were detected by western blot and RT-PCR. RESULTS AND CONCLUSION: Tumor stem cell spheres were successfully isolated by the serum-free suspension culture. The expression rate of CD44+CD24-on the surface of the third-generation PC-3 human prostate cancer stem cells was (85.69±8.96) ％, indicating that the cultured tumor stem cell spheres overexpressed the phenotype of tumor stem cells. At 48 hours after transfection, the expression of Id2 gene and protein was significantly lower in the shRNA-Id2 transfection group than the non-transfection group (P < 0.05), indicating that the expression of Id2 was successfully interfered with the expression of PC-3 prostate cancer stem cells. The invasive ability of the cells in the shRNA-Id2 transfection group was significantly lower than that in the non-transfection group (P < 0.05). Western blot and RT-PCR detection showed that the expression of E-cadherin, an epithelial marker of PC-3 prostate cancer stem cells, in the shRNA-Id2 transfection group was significantly higher than that in non-transfection group (P < 0.05), while the expression of vimentin, a marker of mesenchymal stem cells, and Twist, a transcription factor regulating cell-mesenchymal transformation, in the shRNA-Id2 transfection group was significantly lower than that in the non-transfection group (P < 0.05). These findings indicate that RNA interference with Id2 gene can inhibit the proliferation and invasion of PC-3 prostate cancer stem cells by regulating the expression of E-cadherin, vimentin and Twist.
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BACKGROUND: Tissue engineering provides a new way for the repair of urinary tissue and organ defects.Urinary tissue engineering has shown a bright prospect.OBJECTIVE: To review the latest research on urinary tissue engineering at national and international level.METHODS: With the keywords of tissue engineering, urology, scaffold, vascularization in Chinese and in English,respectively, a computer-based search for articles published from January 2000 to January 2016 was performed in CNKI and PubMed databases. The articles addressing urology tissue engineering, scaffolds and vascularization were collected,summarized and analyzed.RESULTS AND CONCLUSION: The selection and cultivation of seed cells, scaffold material performance, tissue construction in vitro, and degree of vascularization all make an important influence on the repair of urinary injuries. As different seed cells hold different biological characteristics, we should make full consideration prior to choosing an appropriate seed cell, so as to pave a good foundation for urinary tissue engineering. Scaffolds with good three-dimensional structure can promote the cell growth and proliferation, tissue in-growth and vascularization.Tissue-engineered materials are superior to traditional repair materials, but still on initial stage, and further large scale trials will be necessary. Moreover, some problems needed to be solved, such as the regenerated tissue with incomplete function different from natural tissues, and regeneration failure caused by biological stent rejection.
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Objective To evaluate the effect of targeted monitoring and comprehensive intervention measures on reducing the occurrence of catheter-associated urinary tract infection(CAUTI)in patients in non-intensive care unit(Non-ICU).Methods In quarter 4 of 2015,patients with indwelling urinary catheter in clinical departments were conducted a baseline survey(before intervention),risk factors for CAUTI in patients were analyzed,targeted monitoring programmes and comprehensive intervention measures were initiated in 2016(after intervention),incidence of CAUTI before and after intervention was compared.Results After taking intervention measures,hand hygiene compliance rate increased from 78.51%in quarter 4 of 2015 to 92.99%in quarter 3 of 2016 and 90.73%in quarter 4 of 2016(x2=7.342,3.998,respectively,both P<0.05),the correct disposal rate of patients' urinary catheterization system increased from 72.83%in quarter 4 of 2015 to 95.44%in quarter 4 of 2016(x2=30.267,P<0.05).A total of 12 067 patients with indwelling urinary catheter were monitored,incidence of CAUTI dropped from 1.03%(24/23 313)in quarter 4 of 2015(before intervention)to 0.53%(14/26 595)in quarter 4 of 2016(after intervention),difference was statistically significant(x2=4.126,P=0.042).Conclusion Improving the quality of urinary catheterization system in patients with indwelling catheter through targeted monitoring can effectively reduce the incidence of CAUTI in patients in Non-ICU.
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BACKGROUND: Vessel extracellular matrix (VECM) is a natural scaffold material obtained from vascular tissues, which can stimulate angiogenesis and accelerate vascularization of tissue-engineered graft, however, the mechanism is poorly understood.OBJECTIVE: To explore the vascularization effects of release of vascular endothelial growth factor (VEGF) from VECM in ureteral reconstitution.DESIGN, TIME AND SETTING: An in vitro cytology observation. The experiment was performed at the Biomedical Engineering Laboratory of First Clinical Medical Science College, Wuhan University, between April and August in 2009.MATERIALS: Abdominal aorta was obtained from 5 rabbits to prepare VECM.METHODS: The VEGF released from VECM in vitro was evaluated by ELISA, the effects of cell proliferation by the released VEGF was detected by MTT colorimetric assay. The defected ureters of rabbits were repaired by homologous VECM in vivo.Then the recovery of the defected ureters and the situation of vasculogenesis were detected at different time point.MAIN OUTCOME MEASURES: The detection of VEGF contents in VECM; and the effects of VECM on vascular endothelial cell proliferation and ureteral reconstitution.RESULTS: In vitro experiment presented that the peak amplitude concentration of VEGF released from VECM in PBS solution was (124.10±1.42) ng/L, which showed proliferative effect on vascular endothelial cells. In vivo, there were some blood vessels on the VECM at 2 weeks after implantation. Epithelial coverage was evident in the lumen of the marginal part of the VECM grafts and the smooth muscle extended from the transition zone. After 8 weeks, the quantity of the blood vessel was increased and the caliber of the blood vessels became wide. There was thickness epithelial lamina in the graft, and the muscle fibers had an organized spatial alignment, forming variably sized bundles. After 16 weeks, there were no significant differences between the regenerative tissue and the normal tissue in morphology.CONCLUSION: The homologous VECM can release VEGF when implanted as tissue engineer biomaterial and might be an ideal replacement biomaterial for ureteral reconstitution.